Apparatus for automatically



Feb. 21, 1956 J. F. MUSE 2,735,498

APPARATUS FOR AUTOMATICALLY FILLING A WELL BORE CONDUIT Filed April 27, 1953 3 Sheets-Sheet 1 IN V EN TOR. JOA/A /-T M055 ,mwam

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Feb. 21, 1956 APPARATUS FOR AUTOMATICALLY FILLING A WELL BORE CONDUIT Filed April 27, 1953 J. F. MUSE ii: v

BY WWW g j 2/ /9 M 5 Sheets-Sheet 2 INVENTOR. J0#/V MUSE Feb. 21, 1956 J. F. MUSE 2,735,498

APPARATUS FOR AUTOMATICALLY FILLING A WELL. BORE CONDUIT Filed April 27, 1953 5 Sheets-Sheet 3 INVENTOR. JOA/A i M055 APPARATUS FDR AUTOMATICALLY FILLING A WELL BORE CONDUIT John F. Muse, Montebello, Califi, assignor to Baker Oil Tools, Inc., Vernon, Calif., a corporation of California Application April 27, 1953, Serial No. 351,397

13 Claims. (Cl. 166-225) The present invention relates to subsurface well bore apparatus, and more particularly to apparatus adapted to form part of a conduit string, such as a casing, liner or drill pipe string, as it is lowered through fluid in the well bore.

In the running of a conduit string in a well bore, it is oftentimes desirable to have the string filled through its bottom portion with the fluid in the bore hole. Despite this desirable objective, the fluid in the conduit may overflow at the top of the hole, wetting the equipment and personnel above ground with drilling mud and the like, thereby rendering working conditions at the .site unsafe and unhealthy. Although automatic filling of the conduit string through its lower portion is allowed to occur, at times it is desirable to prevent such upward flow of fluid, as in cementing a string of well casing in bore holes or in preventing reverse fluid flow in a string of drill pipe to forestall blowout conditions.

Accordingly, it is an object of the present invention to provide improved apparatusto be incorporated in a conduit string, that allows the conduit string to fill automatically with the well bore fluid, but in which the rate of filling is retarded to preclude any tendency for the fluid to overflow the conduitstring at the top of the well bore.

Another object of the invention is to provide apparatus of the character indicated, toallow automatic filling at a retarded rate of theconduit string through its lower portion, in which upward flow of fluid through the conduit stn'ng can be prevented whenever desired.

A further object of the invention is to provide apparatus to be incorporated in a conduit string that allows automatic filling of the conduit string through its lower portion at a retarded rate, in which flow of fluid downwardly through the conduit string can occur at an unretarded rate, and in which upward flow of fluid through the conduit string can be prevented under the control of the operator.

Referring to the drawings:

Figure 1 is a longitudinal section through an apparatus being lowered through a well bore;

Fig. 2 is a cross-section taken along the line 22 on Fig. 1;

Fig. 3 is a cross-section taken along the line 3-3 on Fig. 1;

Fig. 4 is a view similar to Fig. 1, with partsof the apparatus in another operative position;

Fig. 5 is a view similar to Fig. .1, .with parts of the apparatus in still another operative position;

Fig. 6 is a longitudinal section through amodified form of apparatus disposed in a well bore.

In its general aspects, the invention contemplates an apparatus to form part of a conduit string to be lowered in a well bore. Therapparatus includes a passage of comparatively small cross-sectional area, to allow the well bore fluid to flow upwardly therethrough and into the conduit string at a retarded rate, in order to preclude overflowing of the well bore fluid from the top of the conduit string as the latteris being lowered in-the well nited States Patent bore. The restricted passage, which may be in the form of an orifice, is incorporated in a back pressure valve mechanism which can open in a downward direction, allowing substantially unretarded pumping or flowing of fluid down through the conduit string. Despite the presence of the orifice, the apparatus includes a device which is capable of closing the orifice, to preclude upward flow of fluid therethrough after the conduit string has been lowered in the well bore to the desired depth, in order that certain substances, such as cementitious material pumped down through and out of the conduit string, are prevented from returning thereinto. If the apparatus is incorporated in a drilling string, it will retard the rate at which the latter will fill with the well bore fluid, because of the presence of the orifice. However, downward pumping of fluid through the drilling string can occur at a substantial unimpeded rate, whereas any tendency for-fluid to flow reversely up through the drilling string is prevented by closing of the orifice.

The apparatus A is illustrated in the drawing as designed for use with a casing string B to be lowered and cemented in a well bore C. It is to be understood, however, that it is applicable to conduit strings in general to be disposed in well bores. As disclosed, the apparatus takes the form of a casing shoe, constituting the terminal portion of the string of well casing. It is to be understood, however, that the specific apparatus could be located in an intermediate portion of the casing string, in which event it would be deemed to be casing collar.

The apparatus disclosed in Figs. 1 to 5, inclusive, includes an outer tubular member it), having an upper threaded box 11 screwed onto the lower pin end 12 of an adjacent casing section B. This casing section is coupled to casing sections (not shown) thereabove extending to the top of the well bore. The tubular member ltlhas a lower plug 13 secured in its lower portion, This lower plug may be made of concrete, which is provided with external ribs 1% cast within companion internal circumferential grooves 15 in the tubular member. The lower end of the plug 13 is preferably rounded in a downward and inward direction, to provide a nose ldfor guiding the casing string past obstructions or restrictions that might be encountered in the well here C asthe casing stringB is lowered thereinto.

Secured within the lower cementitious plug 13 is a lower valve housing 17, that includes a ball valve stop member 18 cast in the plug and having inwardly projecting, circumferentially spaced lugs or fingers 19 on which a ball valve member 2% is adapted to rest. This stop member 18 is held ina downward direction within the plug 13 by a cylindrical housing section 21 which supports the lower portion of a spider 22, having a lower flange 23 extending outwardly into engagement with the wall of the tubular member 10. This spider has circumferentially spaced longitudinally extending ribs 24 extending upwardly therefrom and merging into an upper flange 25 extending radially outward into engagement with the wall of the tubular member 10. This radial flange 25 is integral with a valve seat portion 26integral .with an intermediate valve housing member 27 having 'cementitious material cast in the tubular member, being secured thereto by its external longitudinally spaced ribs 33 received withinlongitudinally spaced circumferential grooves 34 in theupper portion of the tubular member.

This plug 32 extends above the ball stop member 30, and also has internal ribs 35 engaged within external grooves 36 in the valve seat member 27, for the purpose of securely anchoring the valve seat member 27, upper housing member 29 and upper ball stop member 30 to the tubular member 10.

The passage 28 through the valve seat housing member 27 is comparatively large, and the passages 37 through the cementitious plugs 13, 32 and the ball stop members 18, 3t} and the spider 22 are also of substantially large diameters and areas, in order that fluids may be pumped down through the casing string B for discharge through the lower end of the shoe A at a comparatively unrestricted rate. It is desired, however, to greatly retard the rate at which fluid can flow upwardly in the casing string as it is being lowered through the fluid in the well bore C. To accomplish this latter objective, a back pressure valve member 38, which may be in the form of a flapper valve, has a central body portion 39 adapted to engage the valve seat 26, the flapper valve member being pivoted to the spider 22, by having its laterally extended ear portion 40 pivotally mounted on a fulcrum or pivot pin 41 secured to spaced lugs 42 depending from the upper flange portion 25 of the spider. The flapper valve member 38 may swing downwardly out of engagement with its seat 26 completely to one side of the tubular member 10, being disposed substantially completely out of the passage 28 through the valve seat 26. Such action can occur as a result of pumping fluid downwardly through the casing string. The flapper valve member 33, however, is urged in an upward direction into engagement with its companion seat 26, as by providing a comparatively light spring 43 that is coiled around the pivot pin 41, one arm 44 of the spring engaging the spider flange 25 and the other arm 45 of the spring engaging the flapper valve 38. When the flapper valve 38 engages its seat 26, leakage therebetween may be precluded by a suitable seal ring 46 in a groove 47 in the valve seat 26 engaging the generally spherical outer peripheral surface 48 of the flapper valve or head member.

As the casing string B is lowered through the fluid in the well bore C, the flapper valve 38 remains in a closed position. However, since it is desired to allow the casing string to fill through its bottom portion with the well bore fluid, a passage is formed through the flapper valve member 33, and, since the rate at which fluid can flow into the casing string is to be retarded, this passage is made of a comparatively small diameter or area. As disclosed, the passage 49 of small area is formed centrally through an orifice member 50 threaded into a threaded bore 51 in the flapper valve member 33, this orifice preferably being disposed coaxial of the apparatus when the flapper valve 33 is in closed position. As a result, as the casing string B is lowered through the fluid in the well bore, such fluid can pass upwardly into the casing string through the hole or passage 49 in the orifice member.

Although the orifice 50 provides a comparatively simple arrangement for retarding the rate at which fluid can flow into the casing string, to preclude overflowing of the casing string at the top of the well bore, it also presents a passage 49 through which the well bore fluid can pass upwardly into the casing string at a later time. If the casing string is to be cemented in the well bore, the cementitious material pumped down the casing string B and out through its lower end should not be permitted to re-enter the casing string. Accordingly, the present invention includes a device for closing the orifice passage 49.

As disclosed, a ball valve member 20 is arranged initially in the upper housing portion 29 of the apparatus. This ball valve member preferably has a specific gravity of a value making it buoyant in cement slurry. The ball valve member 20 also preferably has a diameter which is slightly less than the diameter of the central passage 28 through the valve seat housing member 27. During the 4 lowering of the apparatus in the Well bore, the fluid passing through the orifice 50 in the flapper valve 38 tends to hold the ball valve member 20 in its upper position against the upper stop lugs or fingers 31 (Fig. 1). There is suflicient area around the ball valve member 20 and between these lugs 31 to allow the well bore fluid to flow freely around the parts and into the casing section B above the tubular member 10.

After the casing string has been lowered to the desired depth in the well bore, the orifice passage 49 is to be closed against any further upward flow of fluid therethrough. All that need be done is to apply pressure to the fluid in the casing string B which will move the ball 29 into the valve seat member 27 and on top of the flapper valve 38. The upper portion 52 of the orifice is preferably concaved or dished, or is provided with a relief portion, so that the lowermost point of the ball does not engage the orifice. Instead, the ball engages the orifice 50 or the flapper valve member around a circumferential extent, to seal the orifice passage 49 against downward flow of fluid therethrough (dotted line position in Fig. 1). It is also to be noted that since the diameter of the ball 20 is substantially equal to the diameter of the passage 28 through the member 27, the ball will eflectively block this passage. Accordingly, the pressure applied to the fluid in the casing string will move the ball 20 and flapper valve 38 in a downward direction, opening the flapper valve fully, as disclosed in Fig. 4, causing the ball 20 to be pumped down past the flapper valve 38 into the portion of the spider 22 below the flapper valve, from where it passes into the lower valve housing portion 21 of the apparatus. Following the cessation of the pumping pressure, the spring 43 will return the flapper valve 38 to its closed position in engagement with the valve seat 26 and the seal ring 46.

The ball valve member 20 is now disposed below the flapper valve 38, its downward movement being limited by its engagement with the lower stop lugs or fingers 19, there being ample passage area around the ball 20 and between the fingers to allow comparatively unrestrained downward pumping or flow of fluid therearound, and out through the lower guide portion 16 of the shoe A.

Fluid can now be circulated down through the casing string B, as, for example, to condition the well bore C preparatory to its being cemented in place. The downward passage of fluid occurs in a comparatively unrestricted manner, since the fluid will displace the flapper valve 38 away from the seat 26 into a wide open position, the fluid then continuing on downwardly through the spider 22 and lower valve housing 21, passing around the ball 20 and out through the casing shoe. This circulating fluid may be followed by the required charge or quantity of cementitious material, such as cement slurry, which will be pumped down through the shoe and past its wide open flapper valve 38, for outward discharge from the shoe, and for upward deposition in the annulus between the casing string B and the wall of the well bore C.

After the required quantity of cement slurry has been pumped out of the casing B, the pressure in the latter can be relieved, the tendency for the cement slurry to flow back into the casing string being prevented by upward movement of the ball valve member 20 into engagement with a lower coaxial seat 53 provided in the flapper valve member 38 (Fig. 5), the lower end of the orifice 50 being disposed sufliciently above this tapered seat, so as not to interfere with full seating and sealing engagement of the ball valve member 20 with the flapper valve member and closing of the orifice passage 49 against upward flow of fluid therethrough. To insure against leakage around the ball valve member 20, a suitable seal ring 54 may be provided in a groove 55 in the flapper valve flapper valve member 38, and that the latteris in engagement with its companion valve seat member 26, to prevent completely upward passage of any fluid throughthe casing shoe. Of course, if it is desired to pump fluid in a downward direction through the casing string B again, the ball valve member 20 will merely shift to a lower position away from engagement with the flapper valve seat-53, and the flapper valve 38 will again swing to one side of the tubular member 10, or to its own position.

For the purpose of preventing possible lodging of the ball valve member 20 in a corner of the tubular member on top of the lower flange 23, in view of the absence of a spider rib 24 at the hinge side of the spider cage, a baflle device, which may be in the form of a leaf spring 56, may be provided in the spider 22,-its upper end being secured to the upper portion of the spider, as by use of screws 57, the spring bowing out into the spider 22 and tubularmember 10, and having its lower finger portion 58 engaging the wall of the tubular member. This spring will preclude the ball from coming to rest within the spider 22, and will insure its downward passage into engagement with the lower ball stop lugs 19.

During lowering of the casing string B inthe well bore C, it is desired to have assurance that the ball valve member 20 will not transfer inadvertently from its upper position above the flapper valve 38 to the lower position. In addition, it is desired to provide some means for indicating to the operator when the transfer is taking place. For that reason, the flapper valve member 38 is initially retained in closed position by a frangible device 59 in the form of one or more shear pins, extending transversely through the spider 22 and into the portion of the flapper valve diametrically opposite its hinge pin 41. Accordingly, the ball valve member 20 cannot'engage the-flapper valve member 38 and shift it to fully open position, unless suflicient pressure is imposed on the fluid inthe casing string to shear the pin 59. This pin may have a shear strength corresponding to a substantial pressure. For example, it may require 300 to 1,000 p. s. i. of pressure imposed on the fluid before it is sheared or disrupted. Accordingly, the ball valve member Ztlwill be retained in its position above the flapper valve 38 until the casing string B has been lowered to the desired depth in the well bore C. Thereafter, pressure imposed on the fluid in the casing section will shift the ball valve member 20 against the flapper valve member 38 to close its orifice 50, the pressure then being increased to a value sufiicient to shear the pin 59 and swing the flapper valve to open position, allowing the ball 20 toby-pass the latter and drop into the lower portion'of the shoe below-the flapper valve member. The fact that a rise in pressure occurs when the pin 59 is to be sheared advises the operator that the ball 20 is engaging the upper portion 52 of the flapper valve 38, and the subsequent drop in this pressure indicates to the operator that the ball has been pumped past the flapper valve 33 to a position therebelow.

In the modification of the invention disclosed in Fig. 6, the upper ball valve stop member and housing 29 have been eliminated, which has the eflect of substantially shortening the apparatus, as well as decreasing its cost. The ball valve member 20 need not be disposed anywhere in the casing string B until the latter has been run to substantially its desired position in the well casing. Thereafter, the ball 20 may be dropped into the casing string from the top of the well bore and will come to rest on top of the flapper valve 38, to close the orifice passage 49 through the latter against downward flow of fluid. Pressure can then be imposed on the fluid in the casing string to a suflicient extent to shear the pin 59, which will then cause the flapper valve 38 to swing to its full open position, allowing the ball valve member to move past it and into the valve housing 21 below the flapper valve. The relieving of the pressure in the casing string allows the flapper valve spring 43 to shift the valve head 38 to its closed position in contact with its companion seat 26.

6 The apparatus can now function in the'same manner as described in connection with the other form of the invention, downward flow of fluid swinging the flapper valve 38 to its open position, and any tendency for fluid to flow reversely up through the shoe A shifting the ball valve member 20 upwardly into engagement with the lower flapper valve seat 53, to close the orifice 49 therethrough.

It is, accordingly, apparent that apparatus has been provided that restricts the flow of well bore fluid into the conduit string as it is being lowered in the well bore, while at the same time preventing, completely, upward flow of fluid in the conduit string at the will of the operator. This latter action can occur merely by causing the orifice closing valve member 20 to be disposed below the flapper valve member 38.

The inventor claims:

1. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon fixed with respect thereto and a valve member movable longitudinally out of engagement from said seat and longitudinally into engagement with said seat to restrict upward flow of fluid through said seat; flow control means providing a restricted passage in said tubular member through which fluid can flow upwardly and bypass said valve member when said valve member engages said seat; and valve means movable to a position across said restricted passage to close said restricted passage.

2. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon fixed with respect thereto and a valve member movable longitudinally out of engagement from said seat and longitudinally into engagement with said seat to restrict upward flow of fluid through said seat; flow control means providing a restricted passage in said tubular member through which fluid can flow upwardly and by-pass said valve member when said valve member engages said seat; and valve means movable upwardly into engagement with said flow control means to close said restricted passage.

3. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable longitudinally out of engagement from said seat and longitudinally into engagement with said seat to restrict upward flow of fluid through said seat; flow control means providing a restricted passage in said tubular member through which fluid can flow upwardly and by-pass said valve member when said valve member engages said seat; and valve means movable downwardly in said tubular member from a position above said valve member, past said valve member, to a position below said valve member to close said restricted passage.

4. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable longitudinally out of engagement from said seat and longitudinally into engagement with said seat to restrict upward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; and valve means movable to a position across said restricted passage to close said restricted passage against upward flow of fluid therethrough.

5. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable into engagement with said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; and valve means movable downwardly in said tubular member past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough.

6. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable upwardly into engagement with said seat to restrict upward flow of fluid through said seat and downwardly from engagement with said seat to allow unrestricted downward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; and valve means movable downwardly in said tubular member into engagement with said valve member and past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough while said valve member engages said seat.

7. in subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member pivotally carried by said tubular member and movable upwardly into engagement with said seat to restrict upward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; and valve means movable downwardly past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough.

8. in subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable into engagement with said seat to restrict upward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; valve means movable downwardly in said tubular memher past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough; and means in said tubular member engageable with said valve means to limit the extent oi movement of said valve means above and below said valve member.

9. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable longitudinally out of engagement from said seat and longitudinally into engagement with said seat to restrict upward flow of fluid through said seat; flow control means providing a restricted passage in said tubular member through which fluid can flow upwardly and by-pass said valve member when said valve member engages said seat; valve means movable to a position across said restricted passage to close said restricted passage; and means releasable by fluid under pressure in said tubular member above said valve member for initially holding said valve member in engagement with said seat.

10. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable longitudinally out of engagement from said seat and longitudinally into engagement with said seat to restrict upward flow of fluid through said seat; flow control means providing a restricted passage in said tubular member through which fluid can flow upwardly and by-pass said valve member when said valve member engages said seat; valve means movable'to a position across said restricted passage to close said restricted passage; and frangible means disruptable by fluid under pressure in said tubular member above said valve member for initially holding said valve member in engagement with said seat.

11. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member movable upwardly into engagement with said seat to restrict upward flow of fluid through said seat and downwardly from engagement with said seat to allow unrestricted downward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; valve means movable downwardly in said tubular member into engagement with said valve member and past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough while said valve member engages said seat; and means releasable by fluid under pressure when said valve means engages an upper portion of said valve member for initially holding said valve member in engagement with said seat.

12. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member pivotally carried by said tubular member and movable upwardly into engagement with said seat to restrict upward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; valve means movable downwardly past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough; and means releasable by fluid under pressure when said valve means engages the upper portion of said valve member for initially holding said valve member in engagement with said seat.

13. In subsurface apparatus for filling a conduit string with fluid in a well bore: a tubular member adapted to form part of the conduit string and having means thereon for attachment to an adjacent conduit string section; said tubular member having a valve seat thereon and a valve member pivotally carried by said tubular member and movable upwardly into engagement with said seat to restrict upward flow of fluid through said seat; said valve member having a restricted passage therethrough through which fluid can flow upwardly in said tubular member; valve means movable downwardly past said valve member and thence upwardly into engagement with said valve member to close said restricted passage against upward flow of fluid therethrough; means releasable by fluid under pressure when said valve means engages the upper portion of said valve member for initially holding said valve member in engagement with said seat; and means in said tubular member engageable with said valve means for limiting the extent of movement of said valve means above and below said valve member.

References Cited in the file of this patent UNITED STATES PATENTS Ragan Apr. 19, 1949 

